Add 'no-relative-imports' rule

Author: jj-ivx

lib/index.js

@@ -2,4 +2,5 @@
 
 module.exports.rules = {
   'no-cross-imports': require('./rules/no-cross-imports'),
+  'no-relative-imports': require('./rules/no-relative-imports'),
 };

lib/rules/no-relative-imports.js

@@ -0,0 +1,56 @@
+'use strict';
+
+const getPackages = require('get-monorepo-packages');
+const { relative, resolve, sep, isAbsolute } = require('path');
+
+module.exports.meta = {
+  type: 'problem',
+  docs: {
+    url:
+      'https://github.com/joshuajaco/eslint-plugin-workspaces/docs/rules/no-relative-imports.md',
+  },
+};
+
+module.exports.schema = [];
+
+const isSubPath = (parent, path) => {
+  const relativePath = relative(parent, path);
+  return relativePath.split(sep)[0] !== '..' && !isAbsolute(relativePath);
+};
+
+const isRelativeImport = (packages, context, node, value) => {
+  packages.forEach(location => {
+    if (
+      !isSubPath(location, context.getFilename()) &&
+      isSubPath(location, resolve(context.getFilename(), value))
+    )
+      context.report({
+        node,
+        message: 'Relative imports of other packages are not allowed',
+      });
+  });
+};
+
+module.exports.create = context => {
+  const packages = getPackages(process.cwd()).map(({ location }) => location);
+
+  return {
+    ImportDeclaration: node => {
+      if (node.source.type === 'Literal') {
+        isRelativeImport(packages, context, node, node.source.value);
+      }
+    },
+    ExpressionStatement: node => {
+      if (
+        node.expression.type === 'CallExpression' &&
+        node.expression.arguments[0].type === 'Literal' &&
+        (node.expression.callee.type === 'Import' ||
+          (node.expression.callee.type === 'Identifier' &&
+            node.expression.callee.name === 'require'))
+      ) {
+        const { value } = node.expression.arguments[0];
+        isRelativeImport(packages, context, node, value);
+      }
+    },
+  };
+};

tests/rules/no-relative-imports.js

@@ -0,0 +1,83 @@
+'use strict';
+
+const ruleTester = require('../ruleTester');
+const rule = require('../../lib/rules/no-relative-imports');
+
+ruleTester.run('no-relative-imports', rule, {
+  valid: [
+    "import workspace from '@test/workspace';",
+    "require('@test/workspace');",
+    "import('@test/workspace');",
+    "import '@test/workspace';",
+    "import '../some/relative/path';",
+    {
+      filename: '/test/workspace',
+      code: "import '../workspace';",
+    },
+    {
+      filename: '/test/workspace',
+      code: "import './some/path';",
+    },
+    {
+      filename: '/test/workspace/some/path',
+      code: "import '../another/path';",
+    },
+  ],
+
+  invalid: [
+    {
+      code: "import workspace from '../../test/workspace';",
+      filename: '/some/path',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+    {
+      code: "require('../../test/workspace');",
+      filename: '/some/path',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+    {
+      code: "import('../../test/workspace');",
+      filename: '/some/path',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+    {
+      code: "import '../../test/workspace';",
+      filename: '/some/path',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+    {
+      code: "import workspace from '../another-workspace';",
+      filename: '/test/workspace',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+    {
+      code: "import workspace from '../another-workspace/testing';",
+      filename: '/test/workspace',
+      errors: [
+        {
+          message: 'Relative imports of other packages are not allowed',
+        },
+      ],
+    },
+  ],
+});